TIDAL AND GEOTHERMAL ENERGY by Mark, Kordell, Grace and Gabrielle
Geothermal Energy
Table of Contents

Geothermal Source of Energy
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U.S. Geothermal Resource Map from Geothermal Basics

Geothermal Power


Introduction:
Geothermal energy is produced from hot rocks underground that heat water to produce steam. People drill holes down into a hot region and steam comes up. The steam then gets purified and is used to drive turbines, which drive electric generators. There may be natural "groundwater" in the hot rocks anyway, or people may need to drill more holes and pump water down to them.


Definiton: Geothermal Energy is a process that uses the inherently high temperature of the Earth's interior to heat water for hot water and energy production.


"A form of energy obtained from within the earth,originating in its core; also,energy produced by extracting the earth's internal heat" from Dictionary.com

Usage: Geothermal technologies use the clean, sustainable heat from the Earth. Geothermal resources include the heat retained in shallow ground, hot water and rock found a few miles beneath the Earth's surface, and extremely high-temperature molten rock called magma located deep in the Earth.

In the News: Recent article 2009 Geothermal Products from Geothermal Source of Energy


Stake Holders: Citizens of Massachusetts can benefit from an increased amount of energy. Geothermal energy is considered "Green" and does not directly release pollutants into the atmosphere. Even though Massachusetts is not in a geothermal 'hot spot' as technology improves, geothermal energy remains a viable source for the people of Massachusetts. Geothermal wells may pose as eyesores. One concern is that geothermal wells drilled far down into sources of ground water may act as entry points for contaminants.

Environmental Impact: Even though the pumping of geothermal sources has no direct effect on the environment, there are stilll other concerns. Geothermal wells are expensive and material-intensive to construct, contributing to pollution. Land cleared for well fields is land that could of been used for farming, housing or wildlife. Wells provide an entry point into deep water for contaminants on the surface. Natural features such as hot springs, mud pools, sinter terraces, geysers, fumaroles (steam vents) and steamin ground can be easily and irreparably, damaged by geothermal development.

Liabilities: Economic- Geothermal energy is not abundant; therefore, well drilling would be expensive and also limited. Expensive wells could lead to increased energy price. This is intolerable in the curent economic situation. This also could take jobs away from the prosperous fossil feul energy industry. Political- Industry is unlikely to invest in an indevour that is not immidately profitable.

Fun Facts:

  • "Geothermal Energy has been around for as long as the Earth has existed. "Geo" means earth, and "thermal" means heat. So, geothermal means earth-heat.
  • Geothermal power is generated in over 20 countries around the world including Iceland, the United States, Italy, France, Lithuania, New Zealand, Mexico, Nicaragua, Costa Rica, Russia, the Philippines, Indonesia, the People's Republic of China and Japan.
  • The entire world resource base of geothermal energy has been calculated in government surveys to be larger than the resource bases of coal, oil, gas and uranium combined.
  • For every 100 meters you go below ground, the temperature of the rock increases about 3 degrees Celsius. Or for every 328 feet below ground, the temperature increases 5.4 degrees Fahrenheit.
  • New facilities can produce electricity from geothermal energy for between 4.5 and 7.3 cents per kilowatt-hour, making it competitive with new conventional fossil fuel-fired power plants.
  • Iceland is situated in an area with a high concentration of volcanoes, making it an ideal location for generating geothermal energy. Over 26% of Iceland's electrical energy is generated from geothermal sources. In addition, geothermal heating is used to heat 87% of homes in Iceland.Icelanders plan to be 100% non-fossil fuel in the near future.
  • Geothermal energy is called a renewable enerygy source because the water is replenished by rainfall, and the heat is continuously produced by the earth.
  • Even though geothermal energy is technically a finite resource, the typical lifetime for geothermal activity around magmatic centers - from 5,000 years to 1,000,000 years - is so long that it is considered a renewable resource.
  • A common way in which geothermal energy is obtained is through tapping into hydrothermal sites, also called geothermal springs. These sites are geologically active places where water seeps into the Earth's crust and is heated by the Earth's interior, rising to the surface as steam." Fun Facts

Advantages:
  • Clean type of energy
  • Renewable energy
  • Could reduce the use of fossil fuels
Article from The New York TIme on geothermal power factories----- more from this site
Disadvantages
  • Disturbing large geological formations, which occurs in geoloical energy harvesting, leads to earthquakes. The magnitude and frequency of such catastrophies has yet to be determined by science.
  • could take 30 years to build the site properly this video
  • "geothermal resources are typically associated with igneous and metamorphic rocks, which are harder than the sedimentary rocks through which most oil and gas wells are drilled." these rocks are harder to drill through, which makes geothermal energy the most difficult for drilling this site

Recent News

~Recovery Act Announcement: President Obama...
~Silver State DIshing Out Golden Geothermal Power



ImageMakerGlobal shows the geothermal energy process in an animated simulation talking about the creation of the energy. (Video)

From DTEEnergyCompany



Tidal Power

Definiton: The generation of electical power through the joining and receding of the tides.

Renewable: Tidal power is renewable because tides continuously join and reced; therefore, power is always being generated. Since water is part of the water cycle, it is never used up which means there is no need for replenishment.

How it Works: A barrage, or huge dam, is built across a river creek or bay. This barrage has gates where it allows the water to flow into the barrage with the incoming tide. The gates then close when the tide begins to go out. This water, trapped inside the barrage, is now called a ‘hydrostatic head’. There are other gates within the barrage that are now opened; these gates contain hydro-electric generators. These generators are now revolved by the outflowing water and power is generated.

Statistics: "the first unit producing enough electricity for 20 to 25 homes; additional units at sites off both Lubec and Eastport to bring production to 4 megawatts, enough to power up more than 1,000 homes by 2016." more from this site

Advantages:
  • Cheap to maintain
  • No waste/ pollution
  • Reliable
Disadvantages: more from this site
  • Disrupts animal migration in oceans
  • needs a big piece of ocean to be cost effective
  • Mud/Sediment builds up behind barrages
  • Only works when the tides are coming in or out- only 10 hours a day

Environmental Impact: "some of the non-monetary costs associated with barrage systems include destruction of habitat, interruption of organisms’ travel routes, potential electromagnetic interference (in the case of species that can sense eelectric fields), and potential acoustic pollution. In addition, hydroelectric systems are well-known for killing fish, and the waste heat that ends up in the water reduces its capacity to store dissolved oxygen, harming not only fish, but all organisms in the affected area. Despite all this, such systems are attractive to many because of their reliance on existing technology and knowledge." Tidal Power-Environmental Impact

Fun Facts:

  • "Tidal energy is the utilization of the sun and moon's gravitational forces - as the tide is the result of their influences.
  • Tidal energy is a type of energy that produces electricity and other forms of power through the use of water.
  • Tidal energy is energy that could be obtained from the changing sea levels.
  • In other words, tidal energy is a direct result of tide shifting from low to high.
  • Tidal energy is one of the oldest forms of energy.
  • Tide mills, in use on the Spanish, French and British coasts, date back to 787 A.D.
  • Tide mills consisted of a storage pond, filled by the incoming tide through a sluice and emptied during the outgoing tide through a water wheel.
  • The tide moves a huge amount of water twice each day and although the tidal energy supply is reliable and plentiful, converting it into useful electrical power is not easy.
  • There are two basic theories on how to convert tides into power. The first involves converting the power of the horizontal movement of the water into electricity. The second involves producing energy from the rise and drop of water levels." Tidal Fun Facts

Recent News

~World's Leading Tidal Energy Centres Forge Alliance
~India Plans Tidal Power Station
~An article from New York on Tidal Power progress from site

Tidal Power Facility
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Tidal Power Potential Map Coastline Of. U.S. from ieee Spectrum